While accessing a collection (XYZ) in a MongoDB, Dremio is showing an error “Field ‘description’ exceeds the size limit of 32000 bytes”. As per Dremio documentation, this is the limit in Dremio.
So, created a copy of the collection (XYZ_Copy) and dropped the “description” field, it is confirmed that the “description” field is deleted from the collection XYZ_Copy. When accessed XYZ_Copy collection from Dremio, it is still showing the same error “Field ‘description’ exceeds the size limit of 32000 bytes” even after the field is dropped.
Deleting a field does not literally delete the field in MongoDB, but UNSET the field. So, internally the field exists, so the meta data. As Dremio accesses metadata, it is finding that field which was deleted (by using UNSET).
After troubleshooting, We are creating a new collection with the needed fields only, instead of copying the whole collection and UNSET a field.
New collection with only the needed is now accessible from Dremio. Working on it . Will keep posted the updates.
Like to share a solution to handle 32000 bytes limit in Dremio.
We had an issue accessing mongoDB Collection havng a value of size 32000 bytes in a field even that field is not selected in Dremio.
Solution to fix this is, Create a view in mongoDB with the fields you need without that 32000 bytes field causing the error. Then, access the view from Dremio, It is Working well.